This session will provide attendees with hands-on experience and in-depth knowledge of using Node.js as a runtime environment and Express.js as a web framework to build scalable and fast backend systems. Additionally, attendees will learn about Passport.js, a popular authentication middleware for Node.js, and how to use Prisma ORM to handle database operations in a type-safe and efficient manner. The session will be conducted by experienced developers who have worked with these technologies and will be able to provide valuable insights and best practices. The session will be interactive and include plenty of opportunities for attendees to ask questions and work on real-world projects.

1. Switch to Backend
Pratik Majumdar
@codadept
MongoDB & Prisma

2. Recap

3. Today’s Agenda
Database Prisma
ORM vs ODM Error Handling
SQL vs NoSQL
MongoDB
CRUD

4. ● Systematic/organized collection of data
● Easily accessible and manageable
● SQL vs NoSQL
Database
MS Excel?

5. • SQL
○ Relational Database
○ Rows and columns
○ Pre-defined schema
○ Eg. MySQL, PostgreSQL
SQL vs NoSQL
Schema vs Schema-less
• NoSQL
○ Non-Relational Database
○ Documents
○ Dynamic schema
○ Eg. MongoDB, Redis

6. SELECT * FROM classroom WHERE id=1;
Need for ORM/ODM?
MySQL
MongoDB
db.classroom.find({id: 1})

7. SELECT
C.CUSTOMER_NAME, C.CITY, C.GRADE,
S.NAME AS "SALESMAN",
O.ORDER_NO, O.ORDER_DATE,
O.PURCHASE_AMT
FROM CUSTOMER C
RIGHT JOIN SALESMAN S
ON S.SALESMAN_ID = C.SALESMAN_ID
LEFT JOIN ORDERS O
ON O.CUSTOMER_ID = C.CUSTOMER_ID
WHERE
O.PURCHASE_AMT >= 2000
AND
C.GRADE IS NOT NULL;
More complex query

8. We don’t write SQL or MongoDB Query Language in our project to access DB.
We use such mappers
ORM
● Object Relational Mapping
● Perform CRUD in Relational DB
ODM
● Object Document Mapping
● Perform CRUD in Non-Relational DB
ORM vs ODM
JS <-> Mapper <-> DB

9. ● Dynamic schema
● Here instead of tables as in SQL DBs we have collections
MongoDB
NoSQL Database
user
{
“username”:
“codadept”,
“scholarId”:
2012005
}
user
{
“firstName”:
“Pratik”,
“scholarId”:
2012005
}

10. Stores data in
BSON - Binary Encoded JSON
MongoDB
Datatype
Has more data types than JSON
JSON
String, Boolean, Number,
Array, Object, null
BSON
String, Boolean, Number
(Integer, Float, Long,
Decimal128...), Array, null,
Date, BinData

11. MongoDB
ObjectId
Each document in the collection has _id field which acts as the unique
identifier for that document.

12. MongoDB
Query using the mongodb CLI
using my_database;
db.createCollection(“user”)
db.user.insert({“id”: 1, “name”:
“Pratik”, “username”: “codadept”})
db.user.find()

13. Prisma
ORM/ODM
Prisma is a auto-generated query-builder for Node.js
Can be used both as ORM or ODM based on the database we use
Other alternatives
For SQL - sequelize
For MongoDB - mongoose

14. Prisma
Why?
● Think as objects and classes instead of complex queries
● Type-safe and auto-completion
● Easy to change databases

15. Prisma
Schema file prisma/schema.prisma
datasource db {
provider = "mongodb"
url = env("DATABASE_URL")
}
generator client {
provider = "prisma-client-js"
}
model Post {
id String @id @default(auto()) @map("_id") @db.ObjectId
title String
content String?
published Boolean @default(false)
author User? @relation(fields: [authorId], references: [id])
authorId String @db.ObjectId
}
model User {
id String @id @default(auto()) @map("_id") @db.ObjectId
email String @unique
name String?
posts Post[]
}

16. Prisma
Components
● Data source: Specifies your database connection (via an
environment variable)
● Generator: Indicates that you want to generate Prisma Client
● Data model: Defines your application models

17. Prisma
Data model
● Represent a table in relational databases or a collection in
MongoDB
● Provide the foundation for the queries in the Prisma Client API

18. Prisma
Accessing your DB with @prisma/client
npm install @prisma/client
This invokes the prisma generate command which which reads your
Prisma schema and generates the Prisma Client code.

19. Prisma
Querying
import { PrismaClient } from '@prisma/client'
const prisma = new PrismaClient()
// Run inside `async` function
const allUsers = await prisma.user.findMany()

20. Let’s code
// Run inside `async` function
const user = await prisma.user.create({
data: {
name: 'Alice',
email: 'alice@prisma.io',
posts: {
create: { title: 'Join us for Prisma Day
2020' },
},
},
})

21. Thank you